Glance
late Middle English (in the sense ‘rebound obliquely’): probably a nasalized form of obsolete glace in the same sense, from Old French glacier ‘to slip’, from glace ‘ice’, based on Latin glacies .
wiktionary
From a conflation of Middle English glacen(“to graze, strike a glancing blow”) and Middle English glenten(“to look askance”). Middle English glacen came from Old French glacier(“to slip, make slippery”), which was a derivative of glace(“ice”). Middle English glenten was derived from Old Norse *glenta(“to shine; look”), which ultimately comes from Proto-Germanic *glintaną(“to shine; look”). Middle English glenten is also the source of glint.
The form of the modern word takes largely after its Latinate parent, save for the medial -n-. On the other hand, the most common sense in modern usage, "to look briefly (at something)", comes from its Germanic parent. The sense "to sparkle" does as well. Most other senses derive from Middle English glacen.
etymonline
glance (v.)
mid-15c., of weapons, "strike obliquely without giving full impact," a nasalized form of glacen "to graze, strike a glancing blow" (c. 1300), from Old French glacier "to slip, make slippery" (compare Old French glaciere "part of a knight's armor meant to deflect blows"), from glace "ice" (see glacial). Sense of "look quickly" (first recorded 1580s) probably was by influence of Middle English glenten "look askance" (see glint (v.)), which also could account for the -n-. Related: Glanced; glancing.
glance (n.)
c. 1500, "a sudden movement producing a flash," from glance (v.). Meaning "brief or hurried look" is from 1590s.
